1. Field of the Invention
The present invention relates to a disc drive apparatus and an electronic device for loading a disc-like recording medium as represented by CD-ROM (Compact Disc-Read Only Memory) and a DVD (Digital Versatile Disc), and more specifically, to a disc drive apparatus and an electronic device with an indication mechanism using a plurality of light emitting elements.
2. Description of the Background Art
Conventionally, some electronic devices such as a disc drive apparatus include an indication mechanism that switches between two colors of illumination for the purpose of indicating the operating state thereof. As one scheme for implementing such an indication mechanism, a two-color LED (light emitting diode) that can emit light in two different colors has been employed. Such a two-color LED is disclosed, for example, in Japanese Patent Laying-Open No. 10-200168 and Japanese Patent Laying-Open No. 10-284757.
Another scheme for implementing such an indication mechanism is to arrange two different types of LEDs (that are each capable of emitting light in a needed color) and to switch between them to cause them to emit light alternatively. Such a method employing two LEDs has an advantage of the great flexibility in selecting the illumination colors and the availability of relatively inexpensive single-color LEDs.
On the other hand, in the above scheme of switching between two LEDs, if thus employed two LEDs (for example, one for emitting red light and the other for emitting blue light) emit light in different luminance from each other, then the brightness of the illumination fluctuates depending on the color as the two LEDs are switched between them. Such a fluctuation in the brightness of illumination is not preferable in sight of indication quality. Accordingly, an indication mechanism is needed, which is capable of suppressing the fluctuation in brightness when the two illuminations are switched between them.
As one method for suppressing such a fluctuation in brightness, as disclosed in Japanese Patent Laying-Open No. 8-223365, the luminance of light emitted from an LED may be adjusted by adjusting the driving current of the LED and others. In order to employ such a method, however, control circuitry for controlling the driving current of an LED may be needed, which will be a factor to increase the manufacturing costs of the electronic device. Therefore, conventionally, it has been difficult to suppress at low costs such a fluctuation in brightness in electronic devices, such as a disc drive apparatus including an indication mechanism switching between two colors of illumination.